When artist Marcel Duchamp first submitted an upside-down urinal as an artwork for an exhibition in 1917, he not only created a furor, but a huge ongoing debate on what constitutes an artwork. Only years later, Fountain is now widely seen as one of the most canonical artworks of the 20th century.
Duchamp's influence is still widely felt. Currently 'The Bride and the Bachelors' exhibition at the Barbican Art Gallery in London features Duchamp's work, plus the work of choreographer Merce Cunningham, composer John Cage, and artists Robert Rauschenberg and Jasper Johns. The exhibition runs until June 9, 2013.